// Copyright 2012 The Go Authors. All rights reserved.// Use of this source code is governed by a BSD-style// license that can be found in the LICENSE file. package bytes_test import ( . "bytes" "fmt" "io" "io/ioutil" "os" "sync" "testing") func TestReader(t *testing.T) { r := NewReader([]byte("0123456789")) tests := []struct { off int64 seek int n int want string wantpos int64 seekerr string }{ {seek: os.SEEK_SET, off: 0, n: 20, want: "0123456789"}, {seek: os.SEEK_SET, off: 1, n: 1, want: "1"}, {seek: os.SEEK_CUR, off: 1, wantpos: 3, n: 2, want: "34"}, {seek: os.SEEK_SET, off: -1, seekerr: "bytes.Reader.Seek: negative position"}, {seek: os.SEEK_SET, off: 1 << 33, wantpos: 1 << 33}, {seek: os.SEEK_CUR, off: 1, wantpos: 1<<33 + 1}, {seek: os.SEEK_SET, n: 5, want: "01234"}, {seek: os.SEEK_CUR, n: 5, want: "56789"}, {seek: os.SEEK_END, off: -1, n: 1, wantpos: 9, want: "9"}, } for i, tt := range tests { pos, err := r.Seek(tt.off, tt.seek) if err == nil && tt.seekerr != "" { t.Errorf("%d. want seek error %q", i, tt.seekerr) continue } if err != nil && err.Error() != tt.seekerr { t.Errorf("%d. seek error = %q; want %q", i, err.Error(), tt.seekerr) continue } if tt.wantpos != 0 && tt.wantpos != pos { t.Errorf("%d. pos = %d, want %d", i, pos, tt.wantpos) } buf := make([]byte, tt.n) n, err := r.Read(buf) if err != nil { t.Errorf("%d. read = %v", i, err) continue } got := string(buf[:n]) if got != tt.want { t.Errorf("%d. got %q; want %q", i, got, tt.want) } }} func TestReadAfterBigSeek(t *testing.T) { r := NewReader([]byte("0123456789")) if _, err := r.Seek(1<<31+5, os.SEEK_SET); err != nil { t.Fatal(err) } if n, err := r.Read(make([]byte, 10)); n != 0 || err != io.EOF { t.Errorf("Read = %d, %v; want 0, EOF", n, err) }} func TestReaderAt(t *testing.T) { r := NewReader([]byte("0123456789")) tests := []struct { off int64 n int want string wanterr interface{} }{ {0, 10, "0123456789", nil}, {1, 10, "123456789", io.EOF}, {1, 9, "123456789", nil}, {11, 10, "", io.EOF}, {0, 0, "", nil}, {-1, 0, "", "bytes.Reader.ReadAt: negative offset"}, } for i, tt := range tests { b := make([]byte, tt.n) rn, err := r.ReadAt(b, tt.off) got := string(b[:rn]) if got != tt.want { t.Errorf("%d. got %q; want %q", i, got, tt.want) } if fmt.Sprintf("%v", err) != fmt.Sprintf("%v", tt.wanterr) { t.Errorf("%d. got error = %v; want %v", i, err, tt.wanterr) } }} func TestReaderAtConcurrent(t *testing.T) { // Test for the race detector, to verify ReadAt doesn't mutate // any state. r := NewReader([]byte("0123456789")) var wg sync.WaitGroup for i := 0; i < 5; i++ { wg.Add(1) go func(i int) { defer wg.Done() var buf [1]byte r.ReadAt(buf[:], int64(i)) }(i) } wg.Wait()} func TestEmptyReaderConcurrent(t *testing.T) { // Test for the race detector, to verify a Read that doesn't yield any bytes // is okay to use from multiple goroutines. This was our historic behavior. // See golang.org/issue/7856 r := NewReader([]byte{}) var wg sync.WaitGroup for i := 0; i < 5; i++ { wg.Add(2) go func() { defer wg.Done() var buf [1]byte r.Read(buf[:]) }() go func() { defer wg.Done() r.Read(nil) }() } wg.Wait()} func TestReaderWriteTo(t *testing.T) { for i := 0; i < 30; i += 3 { var l int if i > 0 { l = len(data) / i } s := data[:l] r := NewReader(testBytes[:l]) var b Buffer n, err := r.WriteTo(&b) if expect := int64(len(s)); n != expect { t.Errorf("got %v; want %v", n, expect) } if err != nil { t.Errorf("for length %d: got error = %v; want nil", l, err) } if b.String() != s { t.Errorf("got string %q; want %q", b.String(), s) } if r.Len() != 0 { t.Errorf("reader contains %v bytes; want 0", r.Len()) } }} func TestReaderLen(t *testing.T) { const data = "hello world" r := NewReader([]byte(data)) if got, want := r.Len(), 11; got != want { t.Errorf("r.Len(): got %d, want %d", got, want) } if n, err := r.Read(make([]byte, 10)); err != nil || n != 10 { t.Errorf("Read failed: read %d %v", n, err) } if got, want := r.Len(), 1; got != want { t.Errorf("r.Len(): got %d, want %d", got, want) } if n, err := r.Read(make([]byte, 1)); err != nil || n != 1 { t.Errorf("Read failed: read %d %v", n, err) } if got, want := r.Len(), 0; got != want { t.Errorf("r.Len(): got %d, want %d", got, want) }} var UnreadRuneErrorTests = []struct { name string f func(*Reader)}{ {"Read", func(r *Reader) { r.Read([]byte{0}) }}, {"ReadByte", func(r *Reader) { r.ReadByte() }}, {"UnreadRune", func(r *Reader) { r.UnreadRune() }}, {"Seek", func(r *Reader) { r.Seek(0, 1) }}, {"WriteTo", func(r *Reader) { r.WriteTo(&Buffer{}) }},} func TestUnreadRuneError(t *testing.T) { for _, tt := range UnreadRuneErrorTests { reader := NewReader([]byte("0123456789")) if _, _, err := reader.ReadRune(); err != nil { // should not happen t.Fatal(err) } tt.f(reader) err := reader.UnreadRune() if err == nil { t.Errorf("Unreading after %s: expected error", tt.name) } }} func TestReaderDoubleUnreadRune(t *testing.T) { buf := NewBuffer([]byte("groucho")) if _, _, err := buf.ReadRune(); err != nil { // should not happen t.Fatal(err) } if err := buf.UnreadByte(); err != nil { // should not happen t.Fatal(err) } if err := buf.UnreadByte(); err == nil { t.Fatal("UnreadByte: expected error, got nil") }} // verify that copying from an empty reader always has the same results,// regardless of the presence of a WriteTo method.func TestReaderCopyNothing(t *testing.T) { type nErr struct { n int64 err error } type justReader struct { io.Reader } type justWriter struct { io.Writer } discard := justWriter{ioutil.Discard} // hide ReadFrom var with, withOut nErr with.n, with.err = io.Copy(discard, NewReader(nil)) withOut.n, withOut.err = io.Copy(discard, justReader{NewReader(nil)}) if with != withOut { t.Errorf("behavior differs: with = %#v; without: %#v", with, withOut) }} // tests that Len is affected by reads, but Size is not.func TestReaderLenSize(t *testing.T) { r := NewReader([]byte("abc")) io.CopyN(ioutil.Discard, r, 1) if r.Len() != 2 { t.Errorf("Len = %d; want 2", r.Len()) } if r.Size() != 3 { t.Errorf("Size = %d; want 3", r.Size()) }}
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package bytes_test
import (
. "bytes"
"fmt"
"io"
"io/ioutil"
"os"
"sync"
"testing"
)
func TestReader(t *testing.T) {
r := NewReader([]byte("0123456789"))
tests := []struct {
off int64
seek int
n int
want string
wantpos int64
seekerr string
}{
{seek: os.SEEK_SET, off: 0, n: 20, want: "0123456789"},
{seek: os.SEEK_SET, off: 1, n: 1, want: "1"},
{seek: os.SEEK_CUR, off: 1, wantpos: 3, n: 2, want: "34"},
{seek: os.SEEK_SET, off: -1, seekerr: "bytes.Reader.Seek: negative position"},
{seek: os.SEEK_SET, off: 1 << 33, wantpos: 1 << 33},
{seek: os.SEEK_CUR, off: 1, wantpos: 1<<33 + 1},
{seek: os.SEEK_SET, n: 5, want: "01234"},
{seek: os.SEEK_CUR, n: 5, want: "56789"},
{seek: os.SEEK_END, off: -1, n: 1, wantpos: 9, want: "9"},
}
for i, tt := range tests {
pos, err := r.Seek(tt.off, tt.seek)
if err == nil && tt.seekerr != "" {
t.Errorf("%d. want seek error %q", i, tt.seekerr)
continue
}
if err != nil && err.Error() != tt.seekerr {
t.Errorf("%d. seek error = %q; want %q", i, err.Error(), tt.seekerr)
continue
}
if tt.wantpos != 0 && tt.wantpos != pos {
t.Errorf("%d. pos = %d, want %d", i, pos, tt.wantpos)
}
buf := make([]byte, tt.n)
n, err := r.Read(buf)
if err != nil {
t.Errorf("%d. read = %v", i, err)
continue
}
got := string(buf[:n])
if got != tt.want {
t.Errorf("%d. got %q; want %q", i, got, tt.want)
}
}
}
func TestReadAfterBigSeek(t *testing.T) {
r := NewReader([]byte("0123456789"))
if _, err := r.Seek(1<<31+5, os.SEEK_SET); err != nil {
t.Fatal(err)
}
if n, err := r.Read(make([]byte, 10)); n != 0 || err != io.EOF {
t.Errorf("Read = %d, %v; want 0, EOF", n, err)
}
}
func TestReaderAt(t *testing.T) {
r := NewReader([]byte("0123456789"))
tests := []struct {
off int64
n int
want string
wanterr interface{}
}{
{0, 10, "0123456789", nil},
{1, 10, "123456789", io.EOF},
{1, 9, "123456789", nil},
{11, 10, "", io.EOF},
{0, 0, "", nil},
{-1, 0, "", "bytes.Reader.ReadAt: negative offset"},
}
for i, tt := range tests {
b := make([]byte, tt.n)
rn, err := r.ReadAt(b, tt.off)
got := string(b[:rn])
if got != tt.want {
t.Errorf("%d. got %q; want %q", i, got, tt.want)
}
if fmt.Sprintf("%v", err) != fmt.Sprintf("%v", tt.wanterr) {
t.Errorf("%d. got error = %v; want %v", i, err, tt.wanterr)
}
}
}
func TestReaderAtConcurrent(t *testing.T) {
// Test for the race detector, to verify ReadAt doesn't mutate
// any state.
r := NewReader([]byte("0123456789"))
var wg sync.WaitGroup
for i := 0; i < 5; i++ {
wg.Add(1)
go func(i int) {
defer wg.Done()
var buf [1]byte
r.ReadAt(buf[:], int64(i))
}(i)
}
wg.Wait()
}
func TestEmptyReaderConcurrent(t *testing.T) {
// Test for the race detector, to verify a Read that doesn't yield any bytes
// is okay to use from multiple goroutines. This was our historic behavior.
// See golang.org/issue/7856
r := NewReader([]byte{})
var wg sync.WaitGroup
for i := 0; i < 5; i++ {
wg.Add(2)
go func() {
defer wg.Done()
var buf [1]byte
r.Read(buf[:])
}()
go func() {
defer wg.Done()
r.Read(nil)
}()
}
wg.Wait()
}
func TestReaderWriteTo(t *testing.T) {
for i := 0; i < 30; i += 3 {
var l int
if i > 0 {
l = len(data) / i
}
s := data[:l]
r := NewReader(testBytes[:l])
var b Buffer
n, err := r.WriteTo(&b)
if expect := int64(len(s)); n != expect {
t.Errorf("got %v; want %v", n, expect)
}
if err != nil {
t.Errorf("for length %d: got error = %v; want nil", l, err)
}
if b.String() != s {
t.Errorf("got string %q; want %q", b.String(), s)
}
if r.Len() != 0 {
t.Errorf("reader contains %v bytes; want 0", r.Len())
}
}
}
func TestReaderLen(t *testing.T) {
const data = "hello world"
r := NewReader([]byte(data))
if got, want := r.Len(), 11; got != want {
t.Errorf("r.Len(): got %d, want %d", got, want)
}
if n, err := r.Read(make([]byte, 10)); err != nil || n != 10 {
t.Errorf("Read failed: read %d %v", n, err)
}
if got, want := r.Len(), 1; got != want {
t.Errorf("r.Len(): got %d, want %d", got, want)
}
if n, err := r.Read(make([]byte, 1)); err != nil || n != 1 {
t.Errorf("Read failed: read %d %v", n, err)
}
if got, want := r.Len(), 0; got != want {
t.Errorf("r.Len(): got %d, want %d", got, want)
}
}
var UnreadRuneErrorTests = []struct {
name string
f func(*Reader)
}{
{"Read", func(r *Reader) { r.Read([]byte{0}) }},
{"ReadByte", func(r *Reader) { r.ReadByte() }},
{"UnreadRune", func(r *Reader) { r.UnreadRune() }},
{"Seek", func(r *Reader) { r.Seek(0, 1) }},
{"WriteTo", func(r *Reader) { r.WriteTo(&Buffer{}) }},
}
func TestUnreadRuneError(t *testing.T) {
for _, tt := range UnreadRuneErrorTests {
reader := NewReader([]byte("0123456789"))
if _, _, err := reader.ReadRune(); err != nil {
// should not happen
t.Fatal(err)
}
tt.f(reader)
err := reader.UnreadRune()
if err == nil {
t.Errorf("Unreading after %s: expected error", tt.name)
}
}
}
func TestReaderDoubleUnreadRune(t *testing.T) {
buf := NewBuffer([]byte("groucho"))
if _, _, err := buf.ReadRune(); err != nil {
// should not happen
t.Fatal(err)
}
if err := buf.UnreadByte(); err != nil {
// should not happen
t.Fatal(err)
}
if err := buf.UnreadByte(); err == nil {
t.Fatal("UnreadByte: expected error, got nil")
}
}
// verify that copying from an empty reader always has the same results,
// regardless of the presence of a WriteTo method.
func TestReaderCopyNothing(t *testing.T) {
type nErr struct {
n int64
err error
}
type justReader struct {
io.Reader
}
type justWriter struct {
io.Writer
}
discard := justWriter{ioutil.Discard} // hide ReadFrom
var with, withOut nErr
with.n, with.err = io.Copy(discard, NewReader(nil))
withOut.n, withOut.err = io.Copy(discard, justReader{NewReader(nil)})
if with != withOut {
t.Errorf("behavior differs: with = %#v; without: %#v", with, withOut)
}
}
// tests that Len is affected by reads, but Size is not.
func TestReaderLenSize(t *testing.T) {
r := NewReader([]byte("abc"))
io.CopyN(ioutil.Discard, r, 1)
if r.Len() != 2 {
t.Errorf("Len = %d; want 2", r.Len())
}
if r.Size() != 3 {
t.Errorf("Size = %d; want 3", r.Size())
}
}